With the two virtually tied in polling, the pitch to Kansas's socially conservative roots could give Roberts the boost he needs to make it past the finish line on Nov. 4. He's struggled to regain the support of conservative voters following a bruising primary fight, and the abortion issue could help him turn out the grassroots disaffected with his candidacy.

Roberts this week launched a radio ad charging Orman “would give President Obama another pro-abortion vote in the Senate,” and noting Orman suggested during a debate that America should move on from the issue. His campaign has also passed out flyers at churches highlighting the issue.

He’s getting help from other allies, too. Susan B. Anthony List, a major national anti-abortion-rights group, has 160 volunteers spread throughout Kansas and Arkansas, another Senate battleground state. The group will have knocked on 25,000 doors in Kansas by Election Day, after expanding its operation to the state in mid-October.

Marjorie Dannenfelser, president of SBA List, said she sees the abortion issue as particularly potent in turning people out to the polls.

"The abortion issue, especially if you're pro-life, it's a motivating issue. It means you try to reorganize your day on Election Day because it means that something like life and death is at stake," she told The Hill.

Her staffers in the state are targeting dropoff voters that care strongly about the issue. She says in particular a candidate’s position on late-term abortions can be a persuading factor that surpasses party lines.

"When you talk about late-term abortion, most people recoil against that — there's an emotional intensity against that idea, it's more persuasive often than some of the subtle economic arguments that are made in a race," she said.

Orman has said he opposes partial-birth abortion and using taxpayer dollars to fund abortions, but hasn’t commented on a specific Senate bill banning late-term abortion.

The strategy could be especially potent in Kansas, which has a long history of pro-life advocacy. Wichita, Kan., was ground zero for the 1991 "Summer of Mercy" anti-abortion-rights protests, which brought thousands of activists to the city to stage sit-ins at abortion clinics and for a huge rally at the Wichita State University stadium.

Since then, anti-abortion-ghts activists and social conservatives more broadly have had an active and organized presence in the state, which has translated to electoral wins for strong social conservatives in the past. During the 2012 election, former Pennsylvania Sen. Rick Santorum (R), who framed himself as the social conservative alternative to Mitt Romney in the presidential race, won the state's caucus with 51 percent support and more than twice as many votes as Romney.

Clay Barker, executive director of the Kansas Republican Party, suggested this organization could boost Roberts at the polls, and that Orman's dismissal of the abortion issue in particular could trigger higher turnout among social conservatives.

"It was a big deal and it will get probably more of them to turn out than they would have otherwise," he said.

Orman's campaign dismissed the attacks focused on abortion as irrelevant, arguing Kansas voters are more concerned with Roberts's absences from committee hearings.

Orman spokesman Mike Phillips told The Hill that the candidate has been forthright with his position on the issue.

“Greg's position on [abortion] has been pretty clear — he was pretty straightforward when he was asked about it at the debate, and nothing has changed," he said.

But even if the abortion issue is just one of many in the race, it’s among the pieces that have fallen into place for Roberts in recent days. He launched an ad featuring beloved Kansas State University football coach Bill Snyder and nabbed the endorsement of his former primary foe, radiologist Milton Wolf, on Thursday.

Still, the most recent independent poll of the race, conducted earlier this week, gave Orman a 2-point lead. Even with all the pieces in place, Roberts is facing an uphill battle heading into Election Day.